The following description is provided to assist the understanding of the reader. None of the information provided or references cited is admitted to be prior art to the present technology.
Oral squamous cell carcinoma (SCC) is one of the most common cancers in the world. Even though the cure rate for some small, primary tumors is high, many patients will develop secondary tumors and the long-term survival rate of this cancer is lower than 60%. Two major etiological factors in oral cavity SCC are tobacco and alcohol, and malignant transformation of the oral cavity tissue is thought to be related to exposure to certain carcinogens found in tobacco. Genetic instability caused by carcinogens leads to aneuploidy, and alterations in the expression and/or mutations in tumor suppressor genes, such as retinoic acid receptor β2 (RARβ2) and p53. In addition, carcinogens induce increased cell proliferation through the activation of additional genes, such as epidermal growth factor receptor (EGFR), cyclooxygenase 2 (Cox-2) or PTGS2, and cyclin D1.